2. Aerobic Gram-Positive Bacilli Part II Division of Medical Technology Carol Larson MSEd, MT(ASCP) Please click audio icon to hear Carol’s narration

3. Gram stain –Morphology –Arrangement Formation of spores Catalase reaction Click icon for audio Differentiation of Major GPR Genera

4. Spore-forming GPR, catalase positive –Bacillus species –Bacillus anthracis –Bacillus cereus Nonspore-forming GPR, catalase positive –Listeria monocytogenes –Corynebacterium species (diphtheroids) –Corynebacterium diphtheriae –Corynebacterium jekeium Click icon for audio GPR Discussed in Student Lab

5. Nonspore-forming GPR, catalase negative –Gardnerella species –Erysipelothrix species –Lactobacillus species Branching Nocardioform GPR –Nocardia species –Streptomyces species Click icon for audio GPR Discussed in This Lecture

6. Pleomorphic gram-variable bacilli Non-sporulating Specimen gram stain: –Clue cells Click icon for audio Gardnerella vaginalis Gram Stain GPR, pleomorphic, Non-spore forming, Catalase negative

7. Does not grow on sheep blood agar Human Blood Agar (V-agar, HBT-agar) –Small colonies with diffuse zone of beta-hemolysis Click icon for audio Gardnerella vaginalis Colony Morphology GPR, pleomorphic, Non-spore forming, Catalase negative

8. Catalase negative Oxidase negative Sodium hippurate usually positive SPS sensitive Click icon for audio Gardnerella vaginalis Identification GPR, pleomorphic, Non-spore forming, Catalase negative

9. Normal vaginal flora Bacterial vaginosis –Polymicrobic infection with Mobiluncus and Bacteroides –Diagnosis Homogeneous, gray discharge Clue cells Amine or fishy odor when add 10% KOH Culture not necessary for diagnosis Click icon for audio Gardnerella vaginalis Clinical Significance GPR, pleomorphic, Non-spore forming, Catalase negative

10. What are the key identification characteristics to determine if Gardnerella vaginalis is the cause of bacterial vaginosis? Examine vaginal specimen for presence of a homogeneous, gray discharge, clue cells on the Gram stain, and an amine or fishy odor when adding 10% KOH. A culture is not recommended, but if done, G. vaginalis grows on V-agar/HBT-agar and it beta hemolytic.

11. Two types –Short GPR –Long, filamentous GPR Non-sporulating Click icon for audio Erysipelothrix rhusiopathiae Gram Stain GPR, pleomorphic, Non-spore forming, Catalase negative

12. Erysipelothrix rhusiopathiae Colony Morphology Grows on BAP –Nonhemolytic or alpha hemolytic Microaerophilic Click icon for audio GPR, pleomorphic, Non-spore forming, Catalase negative

13. Catalase negative Motility –Nonmotile –Test-tube brush growth pattern in semisolid motility tube at 48 hours H 2 S positive in KIA/TSI (only GPR) Sucrose non“F” Click icon for audio Erysipelothrix rhusiopathiae Identification GPR, pleomorphic, Non-spore forming, Catalase negative

14. Zoonotic –Swine erysipelas (fatal to pigs) Man – skin disease –Erysipelas –Direct contact with infected animal –Rarely disseminates causing septicemia with arthritis or endocarditis Click icon for audio Erysipelothrix rhusiopathiae Clinical Significance GPR, pleomorphic, Non-spore forming, Catalase negative

15. What are the key biochemical reactions that identify Erysipelothrix rhusiopathiae? Two gram stain morphologies (GPR), two colony types on SBA, catalase negative, H2S positive, test-tube brush pattern in motility tube, sucrose non“F”

16. Two types –Long slender GPR in chains –Short GPCB Non-sporulating Click icon for audio Lactobacillus species Gram Stain GPR, pleomorphic, Non-spore forming, Catalase negative

17. Grows on BAP –Multiple colony morphologies –Nonhemolytic or alpha hemolytic Microaerophilic Click icon for audio Lactobacillus species Colony Morphology GPR, pleomorphic, Non-spore forming, Catalase negative

18. Catalase negative Sucrose “F” Vancomycin “R” Click icon for audio Lactobacillus species Identification GPR, pleomorphic, Non-spore forming, Catalase negative

19. Lactobacillus species Clinical Significance Normal flora –Mouth –GI tract –Female vaginal tract Rarely pathogenic –Endocarditis –Meningitis Click icon for audio GPR, pleomorphic, Non-spore forming, Catalase negative

20. What is the clinical significance of Lactobacillus species? It is considered normal flora of the mouth, gastrointestinal tract, and female genital tract

21. Nonspore-forming GPR, catalase negative –Gardnerella species –Erysipelothrix species –Lactobacillus species Click icon for audio Review

22. Actinomycetes –Nocardia species –Streptomyces species Click icon for audio Branching Nocardioform GPR

23. Nocardia species Gram Stain Pleomorphic, branching, fine, delicate filaments with fragmentation GPR Often appears beaded Click icon for audio Branching Nocardioform GPR

24. Grows on SBA, Mycology media and LJ media Aerobic growth appears at 3-30 days Waxy, bumpy or velvety rugose forms, yellow to orange colonies Click icon for audio Nocardia species Colony Morphology Branching Nocardioform GPR

25. Nocardia species Identification Partially acid-fast positive Presence of granules in specimen Catalase positive Click icon for audio Branching Nocardioform GPR

26. Nocardia species Clinical Significance Habitat: soil and water Mycetoma (actinomycetoma) –Tissue swelling –Draining sinus tracts –Presence of granules Immunocompromised patients –Pulmonary and disseminated infections Click icon for audio Branching Nocardioform GPR

27. What is the key characteristic in identifying Nocardia species? Branching GPR that is partially acid fast positive

28. What primary disease does Nocardia cause and what 3 symptoms are seen? Mycetoma (aka actinomycetoma). Triad of symptoms: tissue swelling, draining sinus tracts, and the presence of granules

29. GPR with extensive branching, chains and spores Does not fragment easily Click icon for audio Streptomyces species Gram Stain Branching Nocardioform GPR

30. Streptomyces species Colony Morphology Grows on SBA, Mycology media and LJ media Aerobic growth appears at 3-30 days Waxy, bumpy or velvety rugose forms, yellow to orange colonies Click icon for audio Branching Nocardioform GPR

31. Acid-fast negative Click icon for audio Streptomyces species Identification Branching Nocardioform GPR

32. Streptomyces species Clinical Significance Habitat: soil and decaying vegetation Mycetoma (actinomycetoma) Rarely: –Pericarditis –Bacteremia –Brain abscess Click icon for audio Branching Nocardioform GPR

33. How can you differentiate Streptomyces from Nocardia? Streptomyces is acid-fast negative and Nocardia is partially acid-fast positive

34. Nonspore-forming GPR, catalase negative –Gardnerella species –Erysipelothrix species –Lactobacillus species Branching Nocardioform GPR –Nocardia species –Streptomyces species Click icon for audio Aerobic GPR Summary

35. Who am I? HBT media shows beta-hemolysis Gram Stain Gardnerella vaginalis Causes Bacterial Vaginitis

36. Who am I? BAP, growth at 2 daysGram Stain Erysipelothrix rhusiopathiae Motility Tube: “test-tube brush” pattern of growth TSI

37. Who am I? LJ agar at 1 weekGram Stain Nocardia species Causes Actinomycetoma Acid Fast Stain